Simulated-to-real benchmarking of acquisition methods in untargeted metabolomics.

Data-Dependent and Data-Independent Acquisition modes (DDA and DIA, respectively) are both widely used to acquire MS2 spectra in untargeted liquid chromatography tandem mass spectrometry (LC-MS/MS) metabolomics analyses. Despite their wide use, little work has been attempted to systematically compare their MS/MS spectral annotation performance in untargeted settings due to the lack of ground truth and the costs involved in running a large number of acquisitions. Here, we present a systematic in silico comparison of these two acquisition methods in untargeted metabolomics by extending our Virtual Metabolomics Mass Spectrometer (ViMMS) framework with a DIA module. Our results show that the performance of these methods varies with the average number of co-eluting ions as the most important factor. At low numbers, DIA outperforms DDA, but at higher numbers, DDA has an advantage as DIA can no longer deal with the large amount of overlapping ion chromatograms. Results from simulation were further validated on an actual mass spectrometer, demonstrating that using ViMMS we can draw conclusions from simulation that translate well into the real world. The versatility of the Virtual Metabolomics Mass Spectrometer (ViMMS) framework in simulating different parameters of both Data-Dependent and Data-Independent Acquisition (DDA and DIA) modes is a key advantage of this work. Researchers can easily explore and compare the performance of different acquisition methods within the ViMMS framework, without the need for expensive and time-consuming experiments with real experimental data. By identifying the strengths and limitations of each acquisition method, researchers can optimize their choice and obtain more accurate and robust results. Furthermore, the ability to simulate and validate results using the ViMMS framework can save significant time and resources, as it eliminates the need for numerous experiments. This work not only provides valuable insights into the performance of DDA and DIA, but it also opens the door for further advancements in LC-MS/MS data acquisition methods.

Can the exercise-based and occupational therapy improve the posture, strength, and mobility in elderly Greek subjects with hip fracture? A non-randomized control trial.

OBJECTIVES: The effects of a rehabilitation program on static balance, mobility, and strength of lower limbs in elderly fallers operated after a hip fracture and non-operated were studied. METHODS: Ninety-one elderly (>65 years) were divided in two groups, the Operated Group (OG, 43 fallers) and the Non-Operated Group (NOG, 48 fallers). Posture during bipedal stance (30s), mobility (Up-and-Go, Falls Efficacy Scale, Berg Balance Scale) and isokinetic strength of several muscular groups in both limbs were evaluated before and after a rehabilitation intervention, consisting in 20 sessions (3 sessions/week) including kinesiotherapy and occupational therapy. RESULTS: After intervention, the average velocity of Center of Pressure displacement decreased significantly for OG and NOG (p<0.005). Similarly, all other variables describing static balance, mobility (p<0.05) and isokinetic strength (p<0.005) were improved significantly for both groups. CONCLUSIONS: The applied intervention led to improvement in static balance, mobility, and strength of lower limbs after hip fracture. Physical and Rehabilitation Medicine physicians should prescribe evidence-based rehabilitation protocols in elderly fallers because they could show just as remarkable improvements as non-operated patients when the program is carefully designed.